The original script contained cameo appearances by Dutch (Arnold Schwarzenegger) and Michael Harrigan (Danny Glover), the protagonists of the previous Predator films. However, these appearances were ultimately cut out.

Danny Trejo's character is named Cuchillo. "Cuchillo" is Spanish for "knife". Many of Trejo's characters in Robert Rodriguez movies have been named after knives or sharp instruments: Machete in Spy Kids, Spy Kids 2: Island of Lost Dreams, and Spy Kids 3-D: Game Over; Razor Charlie and Razor Eddie in From Dusk Till Dawn, From Dusk Till Dawn 2: Texas Blood Money, and From Dusk Till Dawn 3: The Hangman's Daughter, Navajas (Spanish for "blades") in Desperado, and he also plays another character called Machete in Machete, a feature length version based on a fake trailer featured in the Robert Rodriguez/[?] Quentin Tarantino collaboration Grindhouse.

Nimród Antal specifically chose Adrien Brody for the main protagonist: "It was a challenge in finding a balance. When we cast Adrien, there were a lot of people going, What? But at the same time, if we cast a Vin Diesel in that role or anyone who is Arnold-esque, we would have been attacked for doing that. So we decided early on to go in a very different direction as far as the casting process, but it turned out fantastic." He also felt the soldiers should be portrayed as wiry tough guys, not burly men like Arnold Schwarzenegger.

The average height of the actors who play the Predator creatures in this film are around 6'6-7", while the actors in the previous films, Kevin Peter Hall and Ian Whyte, were 7'2½" and 7'1" tall, respectively.

According to Robert Rodriguez, the title of Predators serves as a double-entendre, describing the alien hunters as well as the ensemble human characters they target: "They could very well kill each other off even if there were no Predators!"

The alien creature that pursues Edwin (Topher Grace) through the jungle during the ambush scene is a slightly modified version of the original, abandoned Predator design from 1987.

As with all of the Predator movies, the female lead always survives.

In none of the Predator movies has any Predator been killed by a firearm.